feat: promote accepted proposals from API

server/domain/formation.go

@@ -2,6 +2,7 @@ package domain
 
 import (
 	"fmt"
+	"sort"
 	"time"
 )
 
@@ -68,5 +69,34 @@ func PrepareProposal(id string, playlist Playlist, formation MatchFormation, ran
 	if err != nil {
 		return PreparedProposal{}, err
 	}
+	if formation.Selection.Region == "" || len(formation.Selection.Players) == 0 || formation.Selection.Players[0].ProtocolVersion < 1 {
+		return PreparedProposal{}, fmt.Errorf("formed match metadata is incomplete")
+	}
+	proposal.Region = formation.Selection.Region
+	proposal.Protocol = formation.Selection.Players[0].ProtocolVersion
+	for _, player := range formation.Selection.Players {
+		if player.ProtocolVersion != proposal.Protocol {
+			return PreparedProposal{}, fmt.Errorf("formed match has mixed protocols")
+		}
+	}
+	assignProposalSlots(&proposal, formation.Teams)
 	return PreparedProposal{Proposal: proposal, CasualLineup: lineup}, nil
 }
+
+func assignProposalSlots(proposal *Proposal, teams Teams) {
+	assign := func(team int, players []Candidate) {
+		ordered := append([]Candidate(nil), players...)
+		sort.Slice(ordered, func(i, j int) bool { return ordered[i].PlayerID < ordered[j].PlayerID })
+		for index, player := range ordered {
+			for participant := range proposal.Participants {
+				if proposal.Participants[participant].PlayerID == player.PlayerID {
+					proposal.Participants[participant].Team = team
+					proposal.Participants[participant].Slot = team*3 + index
+					break
+				}
+			}
+		}
+	}
+	assign(0, teams.Team0)
+	assign(1, teams.Team1)
+}

server/domain/formation_test.go

@@ -10,7 +10,7 @@ func testFormation(t *testing.T, count int) MatchFormation {
 	now := time.Unix(1000, 0)
 	players := make([]Candidate, count)
 	for i := range players {
-		players[i] = Candidate{TicketID: string(rune('a' + i)), PlayerID: string(rune('p' + i)), Rating: 1500, EnqueuedAt: now, PredictedRTT: map[string]float64{"EU": 40}}
+		players[i] = Candidate{TicketID: string(rune('a' + i)), PlayerID: string(rune('p' + i)), ProtocolVersion: 1, Rating: 1500, EnqueuedAt: now, PredictedRTT: map[string]float64{"EU": 40}}
 	}
 	selection, err := SelectCandidates(players[0], players[1:], count, now)
 	if err != nil {
@@ -31,6 +31,9 @@ func TestPrepareProposalBuildsCasualLineupBeforeCreatingProposal(t *testing.T) {
 	if prepared.Proposal.Playlist != Casual || len(prepared.Proposal.Participants) != 2 || len(prepared.CasualLineup) != 6 {
 		t.Fatalf("prepared casual proposal = %+v", prepared)
 	}
+	if prepared.Proposal.Region != "EU" || prepared.Proposal.Protocol != 1 || prepared.Proposal.Participants[0].Slot == prepared.Proposal.Participants[1].Slot || prepared.Proposal.Participants[0].Team == prepared.Proposal.Participants[1].Team {
+		t.Fatalf("prepared proposal did not retain deterministic topology: %+v", prepared.Proposal)
+	}
 	humans := 0
 	teams := map[int]bool{}
 	for _, slot := range prepared.CasualLineup {

server/domain/proposal.go

@@ -34,11 +34,15 @@ const (
 type ProposalParticipant struct {
 	PlayerID string
 	Response Response
+	Team     int
+	Slot     int
 }
 
 type Proposal struct {
 	ProposalID   string
 	Playlist     Playlist
+	Region       string
+	Protocol     int
 	Participants []ProposalParticipant
 	State        State
 	Revision     uint64